//对case后加大括号对break影响进行测试


//正常使用
#ifdef a
#include<stdio.h>
int main() {
	int select;
	scanf("%d", &select);
	int a, b, c;
	a = 1, b = 2, c = 3;
	switch (select) {
	case 1:
		printf("%d\n", a);
		break;
	case 2:
		printf("%d\n", b);
		break;
	default:
		printf("%d\n", c);
		break;
	}

	return 0;
}
#endif


//可以正常运行
#ifdef a
#include<stdio.h>
int main() {
	int select;
	scanf("%d", &select);
	switch (select) {
	case 1: {

	}
		int a = 1;
		printf("%d\n", a);
		break;
	case 2: {

	}
		int b = 2;
		printf("%d\n", b);
		break;
	default: {

	}
		   int c = 3;
		printf("%d\n", c);
		break;
	}
	return 0;
}
#endif



//没有break，连续运行，直到结束
#ifdef a
#include<stdio.h>
int main() {
	int select;
	scanf("%d", &select);
	switch (select) {
	case 1: {

	}
		  int a = 1;
		  printf("%d\n", a);
	case 2: {

	}
		  int b = 2;
		  printf("%d\n", b);
	default: {

	}
		   int c = 3;
		   printf("%d\n", c);
		   break;
	}
	return 0;
}
#endif


//下面两个break方式效果相同,没有的话需要连续运行
#ifdef a
#include<stdio.h>
int main() {
	int select;
	scanf("%d", &select);
	switch (select) {
	case 1: {
		int a = 1;
		printf("%d\n", a);
		break;

	}
	case 2: {
		int b = 2;
		printf("%d\n", b);

	}
		  break;
	default: {
		int c = 3;
		printf("%d\n", c);
	}
		   break;
	}
	return 0;
}
#endif